Relational database management systems (“RDBMSs”) typically include features that allow users to select different options that may be used to provide increased efficiency for the operations of the RDBMSs. These will allow users to take advantage of potential operational improvements that relate to characteristics of the data and/or systems An example of such a user-selectable feature is where, for a page-based RDBMS, a user is able to define tables as being append mode or otherwise. When a row is added to an append mode table the new row is added at the end of the table, there is no search for unused space in the table. In the case where the relational database is organized in pages, such an append mode table insert is defined to occur in the last page in the table. An example of such a system is the DB2™ relational database management system of International Business Machines Corporation. A table in a DB2™ database may be defined to be an append mode table, as is described above.
In addition, an RDBMS may carry out an insert operation on a table using an append mode insert operation in certain circumstances, whether or not the table itself has been specified to be append mode by a user. For example, where the existing pages in a relational table have only a limited amount of free space, the RDBMS may determine that the most efficient way to insert rows in the table is by an append mode insert operation (the rows are added at the end of the table).
Where an append mode functionality is implemented in a page-oriented relational database system that is concurrent, different processes (or agents) may seek to concurrently insert rows in the table. As a result of the concurrency support in such systems, the processes seeking to insert data in the last page of the table will each seek to acquire exclusive rights to write to that page before executing the insert operation. Different processes will be potentially delayed in accessing the table as a result of the mechanisms used to implement the concurrency in the relational database management system. In highly contentious environments there will be multiple processes seeking access which may reduce the efficiency of the relational append mode insert operation.
It is therefore desirable to provide a method, system and computer program product for use in a relational database management system to improve the efficiency of concurrent append mode insert operations carried out in a relational database system.